Is your dog, cat, or other pet acting strange? They might not have a physical illness, but they still need help. There are a few psychological disorders your pet might be suffering from — and they’re totally treatable.

Do animals really develop psychological disorders?

Technically, animals can’t be diagnosed with a specific mental disorder the way humans can. There isn’t a DSM-5 for dogs. However, pets and wild animals alike can present with abnormal behaviors signaling severe psychological distress.

Next: What does a seriously stressed pet look like?

When your pet starts acting weirder than usual

There’s a lot we know about animal behavior, especially widely domesticated animals, such as cats and dogs. Still, sometimes they just do strange things we don’t understand. Maybe your cat feels the need to sprint around the house at 2 a.m. for the fun of it. They’re probably fine.

However, consistent, abnormal behaviors — especially related to how they interact with you on a daily basis — might mean there’s something more serious going on.

Next: There are nervous dogs, and then there are these.

Anxiety

Dogs can experience anxiety. | Photodisc/iStock/Getty Images

The most common causes of anxiety in dogs are aging, separation, and fear. Your dog might become anxious temporarily when you leave the house and become more anxious over time if they feel abandoned. Unfortunately, it’s common for dogs experiencing anxiety to become aggressive, which can become dangerous if untreated.

Obsessive-compulsive disorder

Dogs can get OCD, too. | Alona Rjabceva/iStock/Getty Images

Even though you can’t technically diagnose a dog, cat, or other animal with OCD, they can display compulsive behaviors that appear irrational. Triggered by frustration or stress, these behaviors in dogs specifically can range from obsessively licking their paws to pacing back and forth for no apparent reason.

Next: Traumatic experiences affect humans as well as their pets.

Post-traumatic stress disorder

Military dogs are at risk of developing PTSD. | JamesYetMingAu-Photography/iStock/Getty Images

As happens with humans, PTSD in a dog or cat results after a traumatic experience. Dogs who accompany soldiers on military missions show symptoms the same way a war veteran might. Being abandoned, losing their owner, abuse, and natural disasters can also trigger PTSD symptoms.

In dogs, this often looks like abnormally destructive behavior, crouching, tucking in their tails, or pinning back their ears.

Next: Dogs get sad — but not usually this sad.

Depression

A dog who’s depressed doesn’t exhibit the same symptoms a person with depression would. Usually, major behavior changes involve a loss of interest in everyday things. If your dog no longer loses his composure upon hearing the word “walk” like he used to or no longer greets you at the door with his tail wagging, it might be time to take a trip to the vet.

Next: Think your pet needs help? Here’s what you can do.

How you can help

Though dogs can provide comfort for people with psychological disorders, can an owner provide therapy for their pet? It might depend on how severe their behaviors are. A vet might be able to offer medications and suggestions. And working with an animal behavior specialist could help correct the behaviors that are dangerous to you or your pet.